Lift



June 16, 1936. N. c. SMART ET AL LIFT Filed Sept. 28, 1934 & INVLNTORS mdU Patented June 16, 1936 UNI TE D STATES PATENT OFFICE LIFT Application September 28, 1934, Serial No. 745,884 In Great Britain October 5, 1 933 6 Claims.

invention relates to lift or like controlling systems, and has for its object the cheapen-ing of such systems whilst at the same time improving in certain points on their reliability.

In connection with certain automatic or semiautomatic lift'controlling systems, it is necessary that the control mechanism shall possess some indication of the position of the lift at any stant. This indication may be employed to determine, for example-the direction in which a lift is to travel when a calling or starting button is pressed, or to give a visual indication of the lifts position, or for like purposes. In this connection it is known to provide facsimile or reduction gearing operated directly or indirectly from the winding drum of a lift, which gearing drives a multi-contact switch affording the required in dications. This method, though fairly certain in action, is costly and requires skilled maintenance.

An alternative known method of affording 'i-n-- dication of a lifts position isto cause the said lift to supply current impulses at particular points in its travel to a group-of non-self-maintained relays each one of which, to remain operated, must receive current continuously, the said relaysoperating or releasing and remaining thus positioned in sequence as the lift passes the said points. The objections to this method are that a current of greater or less dimensions is continuously employed in maintaining some or all -of the relays energized, and that should this current supply fail, then even if the lift does not move, restoration of the current does not re-energize the relays necessary to afford indication of the lifts position.

According to the present invention, the impulses transmitted by the lift are received by, and operate, a chain of relays of a self-maintaining or two-position type such as that disclosed in British specification No. 354,847. The direction of operation of the chain is determined by the direction of travel of the lift.

Further, means are provided, according to the invention, whereby a facsimile of the position of a lift in a shaft is afforded by 'a group of relays each adapted to maintain itself in either one or two positions without the continuous use of current, the said group receiving an impulse of current each time the lift passes a predetermined point or points in the shaft.

Reference is now directed to the accompanying drawing of a circuit diagram of a system embodying the invention, which shows means for controlling a lift serving seven floors. All relays are shown in the positions occupied when the lift is situated at the bottom floor. The lift L is -suspended on a cable having a counterweight LW, the cable passing over -a drum -D operated by the motor M, a brake band BB being arranged to be-operated by the brake magnet BM for releasing the brake for movement of the lift. The direction of travel of the lift is controlled by the two direction contactors UD and DD which control the motor 'M'in cooperation with a slowdown or speed-control contactor DS. Each floor is provided with a gate switch GA to GG connected in series by leads 3A to 3G and by lead 3L in series with a lift or emergency switch GL on the lift car. These gate switches GL'and GA to "GG when closed complete the circuit of a gate relay FL operating a contact fll which will be normally closed when all the gate switches GL and GA to GG are closed.

Within the lift car andat each floor, floor push buttons PA to PG are arranged to operate circuit closing contact members connected by a common lead 4P through contacts 5113,4117: and um with a positive potential at SF, and by individual leads 6A to "6G with corresponding call storage relays CA 'to CG.

Each call storage relay CA to CG operates a corresponding cont actor cal to 091 to close a retaining circuit for the respective relays through leads la to lg connected with a common lead 8 passing through a normally closed contact Sdz to positive potential at 9.

' Each of the call storage relays CA to CG is arranged to control the operation of two contactors cae, 'C'Ga to cgz, egg in a plurality of interconnected circuits arranged to normally short circuit the direction relays UP and DN. One main short circuiting lead 10 extends from contacts cat to the lead H on the negative side of the down direction relay DN which is connected through lead I! and contacts 11421, with the positive potential, while the contact 093 at the other endo'f the "series of contacts is connected through a main short circuiti-ng lead 13 with the lead 14 on the negative side of the up direction relay UP, which, as will be seen is connected through lead [5 and contacts dm with the positive potent-ial.

In order to facilitate changing the point of application of the positive potential for the respective short circuits of the direction relays UP and DN, the contacts cm and caa to car and 093 are interconnected by leads lfia. to Ito and I'll) to Hg with the respective positive potential leads IB'a to I 89, the opposite ends of the latter being arranged, by means of individual contacts, to be 55 further connected by contacts faz and fbs to 17s and interconnecting leads l9a to l9a with the positive potential at 20.

It will be seen that the lower series of contacts can to cga, operated by the call storage relays CA to CG, are arranged to cooperate with upper contact for the short circuit and lower contacts connected by leads Zia to Zlg with a common lead 22 for carrying positive potential to the retardation relay SD, which is arranged to operate contacts sd1, sclz, sd; and stir, the contacts 8611 pro-- viding a holding circuit for the retardation relay SD from the timing device circuit TD.

It will be seen that the up direction relay UP operates contacts upi, upz, up: and 11.104. Of these contacts upz connects leads 23 from positive potential through contacts fll to lead 24 connected to the up drive contactor UD and then through the common lead 25 to the brake relay E and to the negative potential. The brake relay E by operating contactor e1 controls the application of positive potential to the brake magnet BM, either directly through lead 26, or through lead 21 and floor relay contacts 1m and lead 28. The contacts 1211 are normally held open by operation of the floor relay NR when the lift car is at any floor, by means of an inductor plate FP, one of which is located in the lift shaft at each floor.

Down direction relay DN, the same as up relay UP, operates four contacts dm, dnz, (ins and dm, the contact dnz closing on the same lead 23 from the contact fll but now to direct positive potential to the down drive contactor DD, then through the common lead 25 to complete the circuit through relay E.

A plurality of counting relays FA to FF inclusive, are provided each counting relay being provided with two magnet coils operating on a two position armature, each armature being adapted to operate a plurality of contacts, the contacts faz and fbs to 173 being operated in sequence for changing the short circuit connections between the leads (8a to l8g according to the position of the lift in the shaft. The counting relays FA to FF also operate certain contacts far to fei and fbz to fiz for interconnecting operating circuits for progressive and successive )peration of the respective counting relays according to whether the lift is traveling up or down the shaft.

For controlling the counting relays FA to FF during up travel of the lift, alternate upper coils of the relays are connected by leads 300., 30c and 30e through connecting leads Mb, 320, 3ld, 32c and contacts fbl and jdi with the upper coils of alternate counting relays, and to an impulse circuit lead 33. The other alternate upper coils of the counting relays, that is, FB, FD and FF being connected by leads 30b, 30d and 30) and by contacts far, fci and fei and leads 3|a, 32b, 3lc, 32d, 31c, 32 with an impulse circuit lead 34.

Similarly the lower coils of the counting relays FA to FF are connected alternately, the counting relay coils FA, FC, and FE being connected through leads 350., 35c and 356 with leads 36b, 31c, 36d, 31c and 36f, by the respective contacts fbz, fez and fiz with impulse circuit lead 38. The other alternate coils of relays FB, FD and FF being similarly connected by leads 35b, 35d and 35 with leads 36c, 31d, 34e, 31f with an impulse lead 39, by contacts Jcz and fez.

The impulse circuit leads 33 and 34 are provided with oppositely placed contacts cooperating with the contactor b2; and impulse circuit leads 38 and 39 are provided with oppositely placed lead 42 which connects with the contacts 1151 10 adapted to be closed by impulse relay NS. Im-

pulse relay NS is adapted to be operated by inductor plates IP located between floors for sending an impulse current to the counting relays for operation thereof to count the floors, that is, by operating the respective contactors faz and fbs to {T3 in sequence according to the direction of travel of the lift, the counting relay coils operated being determined by the contacts up; and dm one or the other operated by the respective direction relays UP, DN to thereby determine the direction and order of sequence of the counting relays FA to FF.

The impulse current lead 42 by means of a branch 43 and contacts In (in the lower position) connects with a lead 44 for actuating a holding relay A which by operating its contact all provides a holding circuit through lead 45 with one coil of a two coil counting control relay B, the circuit therethrough being completed through a lead 46 to the impulse relay contacts nsi when the latter are released by impulse relay NS.

Operation of the counting control relay B brings into operation the second coil of this relay through the lead 41 to hold the relay operating when the holding relay A is released. As explained later, this provides for the impulse operation in succession of the counting relays FA to FF by the successive switching of the impulse current when the contacts bz and b3 are shifted from one contact position to the other on the respective leads 33, 34 and 38, 39.

There is a possibility that the counting relays FA to FF may lose step with the lift in the shaft or get out of synchronism therewith and for the purpose of restoring proper timing relation, a contactor TL is arranged at the top of the shaft to be operated by the lift when it reaches the end of its upward travel, this contactor by closing its contacts supplies positive potential 50 through leads 33T and 34T, which, it will be seen, are connected at the contacts bz with the leads 33 and 34, to the respective counting relays so that those out of step will be operated through their upper coils to restore them to synchronism.

Similarly, at the bottom of the shaft the contactor BL when operated by the lift reaching the end of its travel downward closes its contacts and supplies positive potential through leads 38B and 39B, which it will be seen are connected at contacts b3 with the leads 38 and 39, to the counting relays FA to FF so that any of them out of step will be operated through their lower coils to restore the relays to synchronism. The counting relays shown in the group FA--FF preferably comprise impulse operated relays of the type shown, for example in British specification No. 354,847.

Assuming that a call for floor 3 is to be made,

a call button PC is depressed momentarily. As shown in the drawing, this button forms one of a number of such buttons PAPG (one for each floor) appearing in the lift carriage, and as explained, floor buttons in the same respective circuits, one at each floor also act to call the lift to the floor at which a buttonahas been depressed. As a result of the depression of the lift floor button PC call storage relay CC is operated from positive SF on contact ups via contact 'dn: lead 4P, push button PC contacts, lead 6C, call relay CC to negative, and the call relay locksat contact 001 through leads 1C and 8 to the positive .9 contact Sdz, so that the button may be released. Contacts 602 and C03 operated by call storage relay CC remove the short-circuit from positive through leads We to l9a, contacts ffa to fas, lead l8a contacts cm, 0113 to cm, 093 and lead I3 across direction .relay UP, causing it to operate positive from contact dm through leads l5 and i4. Contact 003 by closing on its lower contact through lead 2 IC and 22 also prepares a circuit to operate retardation relay SD from positive 20 at ff; as explained later.

Upon operation of direction relay UP the following contacts become effective. Contact am opens the positive to lead I2 and prevents false operation of direction relay DN. Contact um closes a circuit from positive at fli, through leads 23 and 24 which operates the up drive contactor unit UD and through lead 25 the brake relay E in series therewith, (see later). Contact Mp3 opens at the positive 5P through lead 4P to the push button circuit and prevents further depression of push buttons from storing calls by removing positive potential from the buttons PA--PG and the like. Contact up; by closing on lead 40 prepares the stepping circuit through lead 42 from contact M1 for the counting relay chain FA-FF.

Brake relay E having operated upon closing of contact upz, contact e1 opens the positive to lead 21 and directs it into lead 26 which energizes the brake magnet BM, removing the brake band BB from the lift motor M, and the latter commences to drive the lift L upwards under the influence of up contactor UD. When the lift has moved away from the floor at which it was standing, floor inductor relay NR is released. This relay NR is of known type, comprising a permanent or electro-magnet and an armature, fixed 'to the lift, the armature being moved as the relay passes an inductor plate FP in the lift shaft. As previously pointed out, when the lift passes some point intermediate between floors, contacts 11.31 are operated momentarily by the impulse inductor relay NS, which is also of the inductor type, but acted upon by inductor plates IP, different from those operating the floor inductor relay NR. When contact ns1 closes, the positive on lead 46 is opened and positive directed through lead 42 to an intermediate relay A which operates via lead 43 and contact In. Contact or is thereby operated and prepares to lock the intermediate holding relay A in series with counting control relay B. The positive from contact 71 812,150 applies potential to the counting chain relay FA via lead 42 contact um, lead 40 and contact b2, leads 33 and 30a thus operating the first counting relay FA to an opposite position from that shown, and by so doing moving the contacts M1 and M2. The contact m1 by closing prepares a circuit to operate counting relay FB at the next impulse. Contact M2 by moving from lead l8a to I 81; transfers the path of the positive from ffs, previously short-circuiting direction relay UP from contact C113 to contact Cbs.

When impulse inductor relay NS releases after passing the first inductor plate IP, contact nsi by closing on lead 46 operates counting control relay B in series with holding relay A via contact 111, thus holding relay A when contact In opens. Contact b1 moved onto the upper contact on lead 4'! prepares to hold counting control relay. B when lead 42 is energized at the next operation of impulseinductor relay NS which will then open the circuit through the upper coil of control relay B and likewise open the holding circuit through lead 45 and contact or of holding relay A. Operation of control relay 13 moves contact b2 onto its lower contact, on lead. 34 which prepares to operate the second counting relay F13.

The lift now passes floor 2 (the second floor inductor plate FP operates floor inductor relay NR but contacts ups being open nothing happens), and later, passing the impulse inductor plate IP between floors 2 and 3 momentarily operates impulse inductor relay NS once more. This-again operates contact ml which by opening the lower contact on lead 46 releases holding relay A and counting control relay B via its second coil. This impulse also operates counting relay FB over the previously described path through up; but now from lead 40 through 172 on the .lower contact, lead 34 and contact fai, leads 32b and 30b.

Operation of counting relay FB moves contact fin to close on leads 3H) and 33 to switch the impulsingcircuit to the upper contact of be and connect with counting relay FC through leads 32c and 300. At the same time contact fbs moves onto the upper contact transfers the previously described short-circuiting path from lead 19a to lead I80 and to contact 003, which is in an operated position (call storage relay CC operated) thus positive from 20 and contact ,ffs through leads 2| 0 and 22 operates retardation relay SD. Upon operation of retardation relay SD contact sdi closes and locks this relay SD to the time delay device through lead TD. Contact Sdz opens and cuts the positive at 9 from lead 8, thus deenergizing call storage relay CC, which releases. Contact sd4 closes and through lead 50 energizes the slow-down contactor DS.

Releasing call storage relay CC releases contacts 002 and C03 which restores the short circuit from positive 20 and contacts ffa on direction relay UP, the latter releases and cuts the circuit of the up drive contactor UD and brake relay E at contact upz. Contact (:03 moving off lead Zlc opens the circuit to retardation relay SD but this is held from the timing device. Brake relay E released, contact e1 opens and cuts the positive through lead 26 but through the lower contact the positive goes to lead 21 and through contact 1m and lead 28 holds brake magnet BM but prepares to release the brake magnet when floor impulse relay NR is operated and opens contact nri.

Through operation of the slow-down contact DS, the lift now commences to slow down, approaching floor 3. When it arrives at the floor, floor inductor relay NR is energized by a floor inductor plate PP and the contact nri opens, deenergizing the brake magnet BM, which releases the brake BB and stops the lift at the required floor.

Retardation relay SD, which is being held by the time delay TD, is shortly released by the time delay circuit, allowing sufficient time, by holding open contact 3613 so that new calls cannot be registered for the lift, for the floor gate at the third floor to be opened. This action, that is, opening the third floor gate, releases gate relay FL, since switch CC, one of the floor gate switches GAGG is opened. It will be understood that 75 I the gate relay FL, may be released by an emer-' gency switch GL located in the lift carriage as the emergency stop button. Release of gate relay FL, with the opening of contact ,fli prevents energization of either the up or down drive contactors UD or DD until all conditions are favorable, as contact fli removes their energizing positive potential from lead 23 and contacts um and dnz.

If a passenger now enters the lift at the third floor and depresses a button necessitating travel in a downward direction, operations occur similar to those already described except that the previously mentioned short-circuit formed by the contacts of call storage relays CA-CG is broken in a different place; that is, so as to open the short circuit on the down direction relay and direction relay DN is this time energized, and due to the operation of the down drive contactor DD by the closing of contact dnz, the lift travels downward. Since contact rim is now closed instead of contact up; the counting relay chain FA to FF is this time impulsed in a manner similar to that already described, but in a reverse direction, the impulses being supplied from contact nsi via contact (1114, lead 4| and contact b3 to the lower coils of the counting relay group FA-FF. This will restore in succession armatures and contacts previously operated by the upper coils.

As there is always a possibility that an impulse may be missed and the counting relay chain FAFF get out of step, means are provided for ensuring restoration of synchronism each time the lift reaches its upper or lower limit of travel. These means are shown as mechanically operated .OlltECtOlS, TL at the top and BL at the bottom If the shaft, the contactor TL being operated by the lift when the lift is at the top floor, and contactor BL when the lift is at the bottom floor. If, for example, the lift should reach the top floor with only counting relays FA, FE and FC operated, the contactor TL will close its contacts. The closure of its contacts by contactor TL directs positive potential through leads 33T, 33 and 34T, 34 supplying positive potential first to relay FD via leads 34, 30a, contact far leads 32b and 3 [0, contact for and leads 32d and 30d. Contact fdi is then closed and the positive from TL through lead 33 similarly operates counting relay FE, which by closing contact fei operates counting relay FF, thus restoring the counting relays to synchronism. A similar action, onlyoperating the counting relay chain in the reverse direction, through leads 38B, 38 and 39B, 39, occurs when the lift reaches the bottom floor, and contactor BL is operated. Other contacts operated by contactors TL or BL could be arranged to open the lift driving circuit in known manner if required.

Several modifications may be made to the system outlined above, without departing from the scope of the invention. For example, each of the relays FA-FF may be of the latching type, i. e. having an armature which when operated by one coil is held in position by a latch, the latch being removed and the armature restored to normal by the energization of a second coil. This type of relay is shown in British specification No. 208,075. Again the relays A and B may be replaced by a simple impulse-operated device similar toa step-by-stepswitch, and adapted to change over a contact for every impulse. Further, the acceleration and deceleration of the lift may be under control of apparatus of the type disclosed in'U. S. application No. 738,963. In addition further contacts of the relays FA-FF may be caused to light indicating lamps in the lift carriage or at the various floors, showing the position of the lift at any instant. Other modifications will be obvious to those skilled in the art, and the invention is to be understood to cover such modifications, subject to the scope of the appended claims.

We claim:

1. In a lift system serving a plurality of floors, up and down direction relays, a plurality of floor push button circuit connections arranged to operate said relays for prearranging the system for the respective up and down movements of the lift, control circuits interconnected by a plurality of contactors, a chain of two-position counting relays for operating the contactors in said circuits so as to arrange the circuits for controlling operation of the respective up and down relays according to the position of the lift and the direction of travel to the floor required and current impulse means arranged to be operated by the lift in passing from floor to floor for operating the counting relays in succession to thereby change the arrangement of said circuit connections according to the floors passed.

2. In a lift system serving a plurality of floors, up and down direction relays, a plurality of floor push button circuit connections for operating said direction relays, interconnected circuits for controlling up and down travel of the lift, a chain 7 of two position counting relays for the respective floors to be served, contactors in said interconnected circuits controlling the up and down direction relays, a plurality of two-position counting relays arranged to operate said contactors for 3 5 changing the circuit connections according to the position of the lift and current impulse means for operating said counting relays in succession as the lift moves from fioor to floor, said counting relays being actuated to assume one position and effect circuit connections in one direction of sequence when the lift is going up and to assume the other position and effect circuit connections in the opposite direction when the lift is going down.

3. In a lift system serving a plurality of floors, a direction relay for up movement and direction relay for down movement of the lift, floor push button circuits and connections for controlling operation of the respective direction relays, interconnected circuits for normally short circuiting said direction relays, a plurality of call storage contactors in said direction relay short circuiting connections for changing the connections for one and opening the short circuit for and operating the other direction relay, call storage relays for respective floors operated by the respective floor push button circuits for operating said call storage contactors, a plurality of counting contactors in said direction relay short circuiting connections for varying the point of application of the short circuiting potential according to the position of the lift, the arrangement being such that one or the other of said direction relays is operated upon operation of a floor push button according to the point of application of the short circuiting potential as determined by the position of the lift and the direction of travel required, a plurality of two-position counting relays for operating said counting contactors and circuits and current impulse means arranged to be operated by the lift in its movement from floor to floor for actuating said two-position counting relays in succession to position the same according 75 to the position of the lift and its direction of travel.

4. In a lift system serving a plurality of floors as in claim 3, a retardation relay having circuit connections arranged to be completed by contactors operated by said call storage relays and by said two-position counting relays, the arrangement being such that the retardation relay is operated automatically when the corresponding counting relay is operated, operation of said retardation relay being arranged to release the operated call storage relay.

5. In a lift system serving a plurality of floors, an up direction relay and a down direction relay for controlling corresponding movements of the lift, a plurality of contactors and circuit connections normally applying potential to short circuit both of said direction relays, the arrangement being such that one or the other of said direction relays is operated by removing the corresponding short circuit according to the contactor operated as determined by the position of the lift and the direction the lift is required to travel, a plurality of two-position counting relays arranged in a, chain for operating certain of said contactors for changing the point of application of the short-circuiting potential in said circuit connections according to the position of the lift, means operated by the lift in passing from floor to floor for supplying current impulses for operating the two-position counting relays in sequence, relays and circuits for determining the direction of sequence operation of said counting relays according to the direction of travel of the lift, floor call storage relays for operating certain of said contactors for removing the corresponding short circuit for the operation of one or the other of said direction relays according to the position of the lift and the direction of travel required and means for reestablishing the short circuit and releasing the corresponding direction relay when the lift reaches the floor of the call storage relay operated.

6. In a lift system serving a plurality of floors as in claim 5, circuit connections cooperating with contactors arranged to be operated by the lift in predetermined extreme positions of travel for supplying potential for automatically operating in succession any of said two-position counting relays that may have become out of step with the lift in its travel to one extreme position or the other to thereby restore synchronism.

- NORMAN CAROL SMART.

BENJAMIN FRANCIS MOSS. 

